[RFC] use OutputClass PCI ID matching for driver selection.

[Dave Airlie]

This series is a replacement for my previous attempt at glamor forcing
different drivers to load.

First it adds the ability to match on PCI ID strings to the OutputClass
stuff. The sections are of the form:

ection "OutputClass"
	Identifier "nouveau"
	Driver "nouveau"
	MatchPCIID "10de:"
EndSection

The PCIID can be a vendor id, or a vendor id:device id list, I'm not sure
if we need to have subvendor/subdevice at all. The format is no 0x and
lower case hex values.

The second patch then break things, by insisting that drivers use this
mechanism to get loaded. I intend if we accept this to add patches to
the drivers to ship an output class file with them so that they all get
loaded on the appropriate hardware.

This will let distros decide using config snippets which drivers they
want to load on what hardware.

Dave.